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Concentrations and chemical forms of potentially toxic metals in road-deposited sediments from different zones of Hangzhou, China 总被引:5,自引:0,他引:5
The 25 road-deposited sediments were collected from five different land-use zones (industrial, residential, commercial, park, and countryside) in Hangzhou, China. The concentrations of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in these samples were determined using the ICP-AES after digestion with the mixture of HNO3-HF-HCl (aqua regia), and chemically fractionated using the modified BCR (the European Community Bureau of Reference) sequential extraction procedure. The highest metal concentration level was detected in the sample from industrial zone and commercial zone having heavy traffic. While the lowest metal level was noted in the street dust sample from residential zone, park, and countryside zone. The mobility sequence based on the sum of the BCR sequential extraction stages was: Zn (80.28%), Pb (78.68%), Cd (77.66%) > Cu (73.34%) > Mn (67.92%) > Co (41.66%) > Ni (30.36%) > Cr (21.56%), Fe (20.86%). Correlation analysis and principal component analysis were applied to the data matrix to evaluate the analytical results and to identify the possible pollution sources of metals. Factor analysis showed that these areas were mainly contaminated by three sources, namely lithology, traffic, and industry. 相似文献
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贵阳城市污水及南明河中氯霉素和四环素类抗生素的特征 总被引:3,自引:4,他引:3
采用固相萃取-高效液相色谱(UV检测)分析了贵阳城市污水、南明河水和沉积物中氯霉素和四环素类抗生素的特征.结果显示,南北两岸污水中氯霉素、土霉素、四环素和金霉素的平均含量分别为27.0、 2.3、 11.0、 1.1 μg·L-1和21.2、 2.1、 9.5、 0.5 μg·L-1,其中以氯霉素的污染为主;污水中抗生素的含量呈现明显的季节变化,这与用水量和疾病特点有关.南明河已广泛受到包括农业、养鱼塘、城市污水等来源的抗生素污染,其中城市污水是最重要的来源,受其影响,污水口下游的抗生素污染尤为严重.河水中氯霉素、土霉素和四环素在冬季的含量范围分别在2.1~19.0、ND~3.0、 0.8~6.8 μg·L-1之间,夏季分别在0.2~1.3、ND~0.03、 0.2~0.3 μg·L-1之间,金霉素只在冬季检出,含量范围在0.09~0.14 μg·L-1之间;沉积物中4种抗生素在冬季的平均含量分别为147.6、 76.6、 99.2和1.6 μg·kg-1;在夏季分别为195.8、 89.1、 34.4和9.0 μg·kg-1.数据表明,河水中抗生素的含量受河水流量及来源特点的影响很大,冬季河水中抗生素的含量明显高于夏季;沉积物中抗生素的季节变化不明显. 相似文献
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黑龙江省2006—2009年城市声环境质量状况及变化趋势分析 总被引:1,自引:0,他引:1
对黑龙江省13个市地2006年-2009年声环境质量的监测数据进行研究,分析了黑龙江省声环境质量状况及变化趋势。黑龙江省城市区域声环境质量主要处于较好和轻度污染状态;城市道路交通环境质量处于好和较好水平;城市各类功能区声环境质量,夜间超标现象仍很严重;交通噪声影响强度最大;社会生活噪声影响范围最广;改善声环境质量仍是今后一项主要工作。 相似文献
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A water quality model for water reuse was made by mathematics induction. The relationship among the reuse rate of treated wastewater(R), pollutant concentration of reused water( Cs ), pollutant concentration of influent( C0), removal efficiency of pollutant in wastewater( E), and the standard of reuse water were discussed in this study. According to the experiment result of a toilet wastewater treatment and reuse with membrane bioreactors, R would be set at less than 40%, on which all the concerned parameters could meet with the reuse water standards. To raise R of reuse water in the toilet, an important way was to improve color removal of the wastewater. 相似文献
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Distribution of heavy metals in sediments of the Pearl River Estuary, Southern China: Implications for sources and historical changes 总被引:2,自引:0,他引:2
The distribution of heavy metals (Pb, Zn, Cd and As) in sediments of the Pearl River Estuary was investigated. The spatial distribution of heavy metals displayed a decreasing pattern from the turbidity maxima to both upstream and downstream of the estuary, which suggested that suspended sediments played an important role in the trace metal distribution in the Pearl River Estuary. In addition, metal concentrations were higher in the west part of the estuary which received most of the pollutants from the Pearl River. In the sediment cores, fluxes of heavy metals were consistent with a predominant anthropogenic input in the period 1970-1990. From the mid-1990s to the 2000s, there was a significant decline in heavy metal pollution. The observed decline has shown the result of pollution control in the Pearl River Delta. However, it is noteworthy that the metal concentrations in the most recent sediment still remained considerably high. Taken together, the enrichment of heavy metals in sediments was largely controlled by anthropogenic pollution. 相似文献
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